The Jupio USB Brand Charger for Nikon / Fuji / Olympus 7.2V-8.4V Batteries V2 is ideal for travel, as it is lightweight. The charger features an LCD screen that provides a charge indication, notifying you of how far your battery has been charged. 

Nikon EN-EL3, EN-EL3e, EN-EL3a, EN-EL20, EN-EL22, EN-EL24, EN-EL9, EN-EL15, EN-EL14

Fujifilm NP-140, Fujifilm NP-W126, Fujifilm NP-W235, Fuji NP-150

Olympus PS-BLS1, PS-BLS5, BLS-50, Olympus PS-BLM1, PS-BLM5, BLN-1, BLH-1, BLX-1

Pentax D-Li50